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Founder, 1929-2014
Speedy Bill
Since 1952
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Moroso 63420 Manifold Filler Neck

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Has (1) 1/2" NPT fitting and (2) 1/4" NPT fittings. Filler neck has a 3/8" hose barb.
Moroso 63420 Manifold Filler Neck

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Q & A

What's in the Box

Makes manifold the highest filling point.  For cooling problems where radiator is mounted low. Fits both right or left applications. Sender mount. Fits GM V8, 90° V6.

  • Locates filler neck at highest point on cars with low-mount radiators to bleed off air
  • Unit can be flipped 180° for either right or left outlet location
  • Includes 1/2" NPT fitting for installing water temperature sending unit and two 1/4" NPT fittings for return lines on popular aftermarket cylinder heads
  • Made of 356-T6 cast aluminum; 3-1/4" high
  • Includes gaskets, bolts and washers, and standard size radiator cap filler neck
  • Cap is NOT included



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